A huge creature is spotted in Tokyo Bay and Japanese Prime Minister Seiji Okochi attempts to reassure his subjects that the monster is too heavy to move onto the land. This assertion is proved terribly untrue and the beast cuts a swathe through Tokyo, leaving devastation in its wake. Deputy Chief Cabinet Secretary Rando Yaguchi leads a task force to uncover the origins of the creature and his enquiries lead to the work of disgraced zoology professor, Goro Maki.